Metal-working machine.



B. T. BROWAND.

METAL WORKING MACHINE.

APPLICATION FILED JUNE 7. 1912.

Patented July 27, 1915;

2 SHEETS-SHEET I.

I! I'IIII I'Hl M w H COLUMBIA FMNOGRAPH cm. WASHINGTON.

B. T. BROWAND.

METAL WORKING MACHINE.

APPLICATION FILED sum: 7. 1912.

1, 148,007. Patented July 27, 1915.

2 SHEETS-SHEET 2.

COLUMBIA PLANDGWH lo-,WASNINGTON. D- C.

BENJAMIN T. BROWAND, OF CLEVELAND, OHIO.

METAL-WORKIN G MACHINE.

Specification of Letters Patent.

Patented July 27, 1915.

Application filed June 7, 1912. Serial No. 702,224.

To all whom it may concern:

Be it known that I, BENJAMIN T. BROW- AND, a citizen of the UnitedStates, residing at Cleveland, in the county of Cuyahoga and State ofOhio, have invented certain new and useful Improvements in Metal-VVorking Machines, of which the following is a specification.

This invention relates to improvements in metal working machinesgenerally, and particularly to that class of such devices employed inthe manufacture of milling cutters, and is designed for the purpose ofmanipulating the tool to undercut or back oil, as it is called, theteeth of-the cutter and to perform this operation automatically. j

More specifically the invention relates to an attachment to be appliedto milling machines, lathes and like devices, and comprises a face platedriven by the live spindle which also drives the cutter blank, togetherwith mechanism properly'supported in a position to cooperate with camsmounted on the face plate andcarrying a cutting tool adapted to engagethe straight edge of the teeth of the blank and cut back the metalbeyond the edge so as to form the cutter with overhanging or back oifteeth.

The invention may be further briefly summarized as consisting in thecombination and construction of parts hereinafter set forth in thefollowing description, drawings and claims.

Referring to the drawings, Figure l is a side elevation of a portion ofa milling machine provided with my device; Fig. 2 is a detail view; Fig.3 shows the device in its relation with respect to, the face plate andthe cutter blank; and Fig. l isatop plan view of the same.

In carrying out the invention any preferred form and construction ofmilling machine or lathe may be supplied with my attachment providedthey possess the necessary features, I have shown in the drawings,however, the device applied to a milling machine, and in thisembodiment, 1 represents the frame of the machine which is providedwiththe' usual-knee or bed 2 and an upper bearing 8 supporting a bracketface of the base.

4 provided with the usual center 5 for supporting the outer end of thearbor upon which the work is mounted. Rotatably mounted in the frame,and partially shown In the drawings, is a suitable cone pulley 6 whichdrives the live spindle member 7 in the usual manner. Secured to thislive spindle is a suitable face plate 8 of ordinary construction exceptthat it is provided, in

and is held at its outer end by the center 5. All the foregoingmechanism is of the usual construction, with the exception of the faceplate'8, this plate being provided with a plurality of rows of holes, asbefore stated. The plate 8 is provided with a plurality .of rows ofholes 12 varying in number according to the number of teeth of thevarious cutters to be backed off on this machine, it being quite obviousthat the number of rows and the number of openings in .each row may bevaried as desired so as to back off cutters of any number of teeth.Secured rigidly in the holes of the proper row of openings 12 are aplurality of cams 13 held in place by suitable nuts l l. There is a camfor each tooth of the cutter blank 11. It is understood that the faceplate 8, together with thecams l3 rotate with the cutter blank.

Slidably mountedLupon the bed 2 is the usual transverse slide 15 havingT-shaped slots 16 therein which receive suitable bolts 17 passing intonotched lugs 18 integral with the base 19 of the cutting toolattachment. This base 19 is provided with a longitudinal opening 20extending from the left end as shown in Fig. 3 for a short distance andthere merging into an opening 21 extending up through the base intoa'longitudinal dove tail recess 22 in the upper Slidably mounted in thisdove tail recess 22 is a dove tail slide 23 having a portion engaging inthe recess 22 and another portion at extending above the base. Securedin the underside of this dove tail slide are two pins 25 which extendinto suitable openings in the base and engage coil springs 26 whichthrust backward against the wall of the base and tend to thrust the dovetail slide to the left, as shown in Figs. 3 and 4. This dove tail slide23 is still further provided with a bearing 27 supporting a hand screw28 provided with a handle 29. The dove tail slide is still furtherprovided with a screw 30, shown in Fig. 1, and in dotted lines in Fig.3, secured in the block and extending into the opening 21 and therepivotally connected to a link 31 pivotally connected to an arm 32 of alever 33 fulcrumed upon a pin 34 secured in the base.

The lever 33 is pivotally connected by a link 35 with a sliding bar 36mounted in a suitable bearing 37 supported in the base and carrying atits outer end a shoe 38 provided with an inclined side face 39, shown inFig. 1. This face 39 is of a suitable length vertically so that it canengage with cams mounted in any row of openings 12 in the face plate 8,as shown clearly in Fig. 1. The lever 33 is still further provided withan arm 40 extending out to a point beyond the main body portion of thebase and there provided with an adjusting screw 41 held in place by alock nut 42 adapted to engage a stop 43 secured in the base in the pathof the screw. By means of this adjustment the normal position of thedove tail slide may be regulated or in other words, the throw of themechanism may be regulated as will later be brought out. Pivotallysecured to the arm 40 is another link 44 pivoted to a sliding bar 45similar in all respects to the sliding bar 36 and having at its outerend a suitable shoe 46. This shoe 46 and the connecting mechanism isutilized by turning the device so that the shoe will engage the cams onthe face plate, in which case, the teeth of an end cutter blank may bebacked off in the same manner in which the peripheral teeth are backedoff, as are shown in this case. Slidably mounted on the upper portion 24of the dove tail slide is a tool slide 47 having on its up per face atransverse dove tail slot 48 which receives the bolt end 49 of the usualtool post 50 in which the tool 51 is mounted.

In operation the machine is set up with the arbor and the cutter blankin place and with the cams regularly spaced and corresponding in numberto the number of teeth in the cutter blank. After this has beenaccomplished, the operator then adjusts the tool so that it will engagethe teeth at the proper point and then adjusts the screw 41 to give theproper movement of the tool on the teeth, that is, to adjust the lever33 when it is operated by a cam, so that it will move the cutting toolin to the proper point and give the proper clearance or backing Off orundercutting necessary, it being quite obvious that as the adjustingscrew 41 is screwed in the lever 33 is rotated in a clockwise direction,and the tool is operated to the right by reason of the dove tail slidebeing shifted to the right, as shown in Fig. 3, so that the amount ofbacking off is less than it would be in case the adjusting screw were inthe position shown in Fig. 4. It is also quite obvious that the springs26 hold the dove tail slide and the cutting tool mounted thereon awayfrom the work. After the machine has been properly adjusted and power isapplied, the rotation of the cutter blank as well as the face plate 8causes the cutting tool to start in at the straight edge of a tooth andthen to be forced in toward the center as the cutter blank rotates withthe live spindle, this being brought about by reason of one of the camsengaging the shoe 38 and causing the lever 33 to be rotated in aclockwise direction, thereby moving the dove tail slide with the tool tothe right, as shown in Figs. 3 and 4. As soon as the cam moves under theshoe and the high points pass the springs normally shift the dove tailslide back to normal position, or in other words move the cutting toolout to normal position to engage the straight edge of the next adjacenttooth. In this way the teeth are automatically backed off or undercut.

Having described my invention, I claim 1. In mechanism for backing oilthe teeth of cutter blanks, means for rotating the cutter blankcomprising a cam member with a plurality of cams therein correspondingto the number of teeth in the cutter blank, said members rotatingtogether, a base secured to the stationary part, a slide mounted in saidbase, a tool support adjustably mounted on said slide, a tool carried bysaid support, means normally tending to shift said tool away from thework, a lever mounted on said base, connections between said lever andsaid slide, a rod slidably mounted in the base, a cam shoe carriedthereby for cooperation with said cams, connections between said rod andsaid lever, said lever when actuated by said cams being adapted to shiftthe tool toward the work to back off the teeth thereof.

2. In mechanism for backing off the teeth of cutter blanks, means forrotating the cutter blank comprising a cam member with a plurality ofcams thereon corresponding to the number of teeth in the cutter blank,said members rotating together, a base secured to the stationary part, aslide mounted in said base, a tool support adjustably mounted on saidslide, a tool carried by said support, means normally tending to shiftsaid tool away from the work, a lever mounted on said and means foradjusting the movement of base, connections between said lever and saidsaid lever. 10 slide, a rod slidably mounted in the base, a In testimonywhereof I aflix my signature cam shoe carried thereby for cooperation inpresence of two witnesses.

with said cams, connections between said rod BENJAMIN T. BROWAND. andsaid lever, said lever when actuated by Witnesses:

said cams being adapted to shift the tool to- G. O. FAR UHARsoN,

ward the work to back off the teeth thereof, EUGENE R. SEITER.

Copies of this'patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. G.

